Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

Hey everyone, I’m Echo, and I’ve been working with voltage transformers (VTs) for 12 years.From tagging along with my mentor doing insulation tests to now leading teams handling all kinds of high-voltage equipment issues — I’ve done a lot of oil refilling in my time. Especially when it comes to 110 kV voltage transformers, oil refill is a key part of daily maintenance. But let’s be honest — it's also one of the biggest time-wasters.A fe

1. IntroductionOutdoor voltage transformers are key equipment for ensuring the safety of electrical apparatus. Scientific and comprehensive test analysis is required to avoid hazards and property losses caused by improper operation. Test analysis can guide the formulation of operation strategies and precautions, ensure the stable operation of equipment, and maximize economic and social benefits.2. Concept of Outdoor Voltage TransformersAn outdoor voltage transformer is essentially an outdoor ste

1. IntroductionFrequent occurrences of PT burnout and primary - side fuse melting in combined transformers lead to inaccurate energy meter measurement and seriously threaten the safe operation of the power grid. This paper focuses on the repeated PT damage and fuse melting issues of a 35 kV combined transformer, investigates the fault causes, proposes solutions, and recovers the incorrect electricity quantity through correction coefficients. This effectively reduces grid losses and mitigates ser

Voltage transformers (PTs) consist of iron cores and winding coils, working similarly to transformers but with small capacity. They convert high voltage to low voltage for protection, measurement and metering devices, widely used in plants/stations. Classified by insulation: dry - type (≤6 kV), cast - type (indoor 3 - 35 kV), oil - immersed (outdoor ≥35 kV), and SF₆ gas - filled (for combined appliances).During substation operation, accidents from PT electromagnetic resonance or in